1. Department of Cardiovascular Medicine; Ome Municipal General Hospital; Tokyo Japan
2. Department of Cardiovascular Medicine; Tokyo Medical and Dental University; Tokyo Japan
3. Department of Cardiovascular Medicine; Minato Japan Red Cross Hospital; Yokohama Japan
4. Department of Cardiovascular Medicine; Tokyo Yamate Medical Center; Tokyo Japan
5. Department of Cardiovascular Medicine; Sakakibara Heart Institute; Tokyo Japan